Information processing device, information processing method, and non-transitory computer readable storage medium

ABSTRACT

An information processing device according to the present application includes an acquisition unit and a determination unit. The acquisition unit acquires time-series position information acquired by a terminal device. The determination unit determines whether relation between one or more pieces of interest position information included in the time-series position information acquired by the acquisition unit and prior or posterior position information in time series satisfies a predetermined criterion, and determines whether to hold the interest position information based on a determination result.

CROSS-REFERENCE TO RELATED APPLICATION(S)

The present application claims priority to and incorporates by referencethe entire contents of Japanese Patent Application No. 2017-139223 filedin Japan on Jul. 18, 2017.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This disclosure relates to an information processing device, aninformation processing method, and a non-transitory computer readablestorage medium.

2. Description of the Related Art

Conventionally, a device that acquires traveling locus information inwhich positions of a moving body in the moving direction and wirelesscommunication state at each of the positions are associated, andreference locus information that is traveling locus information on themoving body or the other moving body having traveled in the past andthat includes a characteristic point the absolute position of which isknown has been disclosed (for example, see Japanese Laid-open PatentPublication No. 2016-99313). Even when the traveling locus informationis deviated from the reference locus information, the device can reducethe deviation by performing filtering set in advance according to thedeviation or the factor of the deviation, on at least one of thetraveling locus information and the reference locus information.

However, in the conventional technology described above, it is notpossible to properly sort the position information.

SUMMARY OF THE INVENTION

According to one innovative aspect of the subject matter described inthis disclosure, an information processing device includes: (i) anacquisition unit that acquires time-series position information acquiredby a terminal device, and (ii) a determination unit that determineswhether relation between one or more pieces of interest positioninformation included in the time-series position information acquired bythe acquisition unit and prior or posterior position information in timeseries satisfies a predetermined criterion, and determines whether tohold the interest position information based on a determination result.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating a configuration of an informationprocessing system 1;

FIG. 2 is a diagram illustrating the contents of position information 32stored in a storage unit 30;

FIG. 3 is a diagram for explaining a process performed by adetermination unit 56 (first example);

FIG. 4 is a diagram for explaining a process performed by thedetermination unit 56 (second example);

FIG. 5 is a flowchart illustrating a flow of processing executed by aserver device 50;

FIGS. 6A and 6B are diagrams each explaining an angle between vectors;

FIG. 7 is a diagram illustrating an example of the contents of positioninformation when a process of the first to third routines is performedon position information at position IDs 1 to N;

FIG. 8 is a diagram illustrating a functional configuration of a serverdevice 50A included in an information processing system 1A of a secondembodiment;

FIG. 9 is a flowchart illustrating a part of the process flow in thesecond embodiment;

FIGS. 10A and 10B are diagrams each explaining a process performed bythe determination unit 56 in a third embodiment (first example); and

FIG. 11 is a diagram for explaining a process performed by thedetermination unit 56 in the third embodiment (second example).

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, embodiments of an information processing device, aninformation processing method, and a computer readable storage medium ofthe present invention will be described in detail with reference to theaccompanying drawings. The information processing device is implementedby one or more processors. The information processing device acquirestime-series position information from a terminal device, determineswhether relation between each piece of position information included inthe time-series position information and the prior or posterior positioninformation in time series satisfies a predetermined criterion, anddetermines whether to hold the position information on the basis of thedetermination result.

For example, holding the position information means to leave theposition information in a storage unit that is managed or accessed bythe information processing device. For example, the time-series positioninformation may or may not be kept at temporally regular intervals.

The information processing device can properly sort the positioninformation by holding the position information that satisfies thepredetermined criterion instead of by holding the position informationthat does not satisfy the predetermined criterion. Hereinafter, theinformation processing device will be described.

1. First Embodiment

In a first embodiment, the predetermined criterion is a criterionindicating that the position information is meaningful between the priorand posterior position information. For example, the predeterminedcriterion includes at least one of a criterion on a time intervalbetween the interest position information and the prior or posteriorposition information in time series, a criterion on a distance betweenthe interest position information and the prior or posterior positioninformation, a criterion on moving speed based on the time interval andthe distance between the interest position information and the prior orposterior position information, and a criterion on an angle between amoving direction toward the interest position information included inthe time-series position information and a moving direction from theinterest position information.

1-1. Configuration of Information Processing System

FIG. 1 is a diagram illustrating a configuration of an informationprocessing system 1 including a terminal device 10 and a server device50 (an example of information processing device). For example, theinformation processing system 1 includes one or more of the terminaldevices 10 and the server device 50. These components communicate witheach other via a network NW. For example, the network NW includes a widearea network (WAN), a local area network (LAN), the Internet, adedicated circuit, a radio base station, a provider, and the like.

1-2. Configuration of Terminal Device

For example, the terminal device 10 is a portable device such as acellular phone like a smartphone and a tablet terminal. For example, theterminal device 10 includes a positioning device 12, a sensor 14, aterminal control unit 20, a transmission control unit 22, acommunication unit 24, and a storage unit 30. The terminal control unit20 and the transmission control unit 22 are implemented when a hardwareprocessor such as a central processing unit (CPU) executes a computerprogram (software) stored in the storage unit 30. These functional unitsmay also be implemented by hardware such as a large scale integratedcircuit (LSI), an application specific integrated circuit (ASIC), afield-programmable gate array (FPGA), and a graphics processing unit(GPU). Software and hardware (including circuitry) may also implementthe functional units in cooperation. For example, the storage unit 30 isimplemented by a hard disk drive (HDD), a flash memory, a random accessmemory (RAM), and the like.

The positioning device 12 includes a global positioning system (GPS)receiver. The positioning device 12 specifies the position of theterminal device 10 (in other words, the position of the user) byperforming positioning based on radio waves the GPS receiver hasreceived from the satellites. The terminal device 10 may also estimatethe position of the terminal device 10 from the position of the radiobase station connected to the communication unit 24.

Examples of the sensor 14 include a triaxial accelerometer, a gyrosensor, a magnetic field sensor, and the like.

For example, the terminal control unit 20 estimates the moving state ofthe terminal device 10 on the basis of information acquired by thesensor 14. The terminal control unit 20 causes the positioning device 12to acquire position information on the terminal device 10 according tothe moving state of the terminal device 10. For example, the terminalcontrol unit 20 causes the positioning device 12 to acquire positioninformation when the terminal device 10 is moving, and does not causethe positioning device 12 to acquire position information when theterminal device 10 is not moving. Consequently, position information onthe terminal device 10 staying at a position within a predeterminedrange will not be acquired.

More specifically, the terminal control unit 20 may cause thepositioning device 12 to acquire position information at a predeterminedtime interval, determine whether the last measured position and thecurrently measured position are separated for a predetermined distanceor more, and when the last measured position and the currently measuredposition are separated for a predetermined distance or more, determineto store the position information in the storage unit 30. However, it isnot limited thereto, and the terminal control unit 20 may store theposition information measured at each predetermined time interval in thestorage unit 30, regardless of the moving state of the terminal device10.

FIG. 2 is a diagram illustrating the contents of position information 32stored in the storage unit 30. As illustrated in FIG. 2, the positioninformation is stored in the storage unit 30 with a predetermined time(for example “+1”) set as the shortest interval. It is to be noted thata particular unit is not mapped to a numeral 1, and the numeralindicates the time for convenience sake. In the above, the positioninformation is not stored when the terminal device 10 is not moving.However, when the time interval from the last measured time is longenough (for example, when time interval is “+5” or more), the positioninformation may be stored in the storage unit 30. In FIG. 2, theposition information acquired at the time t+8 is the same as theposition information acquired at the time t+3, but because the timeinterval between the time t+3 and the time t+8 is long enough, theposition information acquired at the time t+8 is held. In FIG. 2, aposition ID is identification information assigned to the positioninformation.

For example, the transmission control unit 22 sends the positioninformation stored in the storage unit 30 to the server device 50 usingthe communication unit 24, when predetermined pieces of the positioninformation are accumulated, or at every predetermined period.

1-3. Configuration of Server Device

For example, the server device 50 includes a communication unit 52, aninformation management unit 54, a determination unit 56, and a storageunit 60. For example, the information management unit 54 and thedetermination unit 56 are implemented when the hardware processor suchas the CPU executes a computer program stored in the storage unit 60.These functional units may also be implemented by hardware such as theLSI, the ASIC, the FPGA, and the GPU. Software and hardware may alsoimplement the functional units in cooperation. For example, the storageunit 60 is implemented by the HDD, the flash memory, the RAM, and thelike.

The information management unit 54 causes the storage unit 60 to storethe position information 32 acquired from the communication unit 24 ofthe terminal device 10 by the communication unit 52.

The determination unit 56 sequentially selects predetermined positioninformation from the position information stored in the storage unit 60(hereinafter, referred to as position information 62) as interestposition information. The determination unit 56 then determines whetherrelation between the interest position information and the prior orposterior position information in time series satisfies thepredetermined criterion, and determines whether to hold the interestposition information based on the determination result. The details ofthe process performed by the determination unit 56 will be describedbelow.

1-4. Process Performed by Determination Unit

The process performed by the determination unit 56 will now bedescribed. FIG. 3 is a diagram for explaining a process performed by thedetermination unit 56 (first example). It is assumed that the positioninformation 62 includes position information (position IDs 1 to 5). Forexample, the determination unit 56 selects the interest positioninformation, the prior position information immediately prior to theinterest position information, and the posterior position informationimmediately posterior to the interest position information. The priorposition information, instead of being position information immediatelyprior to the interest position information, may be position informationacquired before the interest position information but one or more. Theposterior position information, instead of being position informationimmediately posterior to the interest position information, may beposition information acquired after next the interest positioninformation or after.

For example, the determination unit 56 selects the position ID 2 as theinterest position information (in the diagram, c: current), the positionID 1 as the prior position information (in the diagram, b: before), andthe position ID 3 as the posterior position information (in the diagram,a: after) at the first process among the repeatedly performed processes.

For example, when determining to hold the interest position informationin the first process, the determination unit 56 selects the position ID3 as the interest position information, the position ID 2 as the priorposition information, and the position ID 4 as the posterior positioninformation in the second process. For example, when determining to holdthe interest position information in the second process, thedetermination unit 56 selects the position ID 4 as the interest positioninformation, the position ID 3 as the prior position information, andthe position ID 5 as the posterior position information in the thirdprocess.

FIG. 4 is a diagram for explaining a process performed by thedetermination unit 56 (second example). Differences from FIG. 3 will nowbe described. For example, when determining not to hold the interestposition information in the first process, the determination unit 56selects the position ID 3 as the interest position information, theposition ID 1 as the prior position information, and the position ID 4as the posterior position information in the second process. Forexample, when determining not to hold the interest position informationin the second process, the determination unit 56 selects the position ID4 as the interest position information, the position ID 1 as the priorposition information, and the position ID 5 as the posterior positioninformation in the third process. When the interest position informationis the first and last position information on the position information62, the interest position information will be held.

In this manner, when determining not to hold the interest positioninformation, the determination unit 56 does not change the priorposition information to the other position information in the nextprocess.

1-5. Details of Process Performed by Determination Unit

FIG. 5 is a flowchart illustrating a flow of processing executed by theserver device 50. It is to be noted that the process sequence in thepresent flowchart is merely an example, and the process sequence may beoptionally changed. Moreover, as described below, an optional process inthe processes may be omitted.

First, the determination unit 56 acquires the position information 62stored in the storage unit 60 (S100). The server device 50 repeats thefollowing processes until there is no position information to beacquired.

As described above, the determination unit 56 sets the prior positioninformation, the interest position information, and the posteriorposition information according to the time series (S102). Next, thedetermination unit 56 determines whether the interest positioninformation is the first or last position information in the time-seriesposition information (S104). When the interest position information isthe first or last position information, the determination unit 56determines to hold the interest position information (S106).

When the interest position information is not the first or last positioninformation, the determination unit 56 determines whether the timeinterval from the interest position information to the posteriorposition information is the first time or more (S108). When the timeinterval from the interest position information to the posteriorposition information is below the first time, the determination unit 56determines not to hold the interest position information (S110).

When the time interval from the interest position information to theposterior position information is the first time or more, thedetermination unit 56 determines whether the time interval from theinterest position information to the posterior position information isthe second time or more (S112). For example, the second time is longerthan the first time. When the time interval from the interest positioninformation to the posterior position information is the second time ormore, the process proceeds to step S106.

When the time interval from the interest position information to theposterior position information is below the second time, thedetermination unit 56 determines whether the time interval from theprior position information to the interest position information is thethird time or more (S114). For example, the third time is longer thanthe first time. For example, the third time may also be the same lengthas the second time. When the time interval from the prior positioninformation to the interest position information is the third time ormore, the process proceeds to step S106.

As S108, S112, or S5114 described above, when the time interval betweenthe interest position information and the prior or posterior positioninformation in time series is a predetermined time or more, the interestposition information will be held. This is because it is assumed thatthe moving degree of the terminal device 10 is a predetermined degree ormore, and the importance of the position information is relatively high.Alternatively, when the time interval between the interest positioninformation and the prior or posterior position information in timeseries is less than a predetermined time, the interest positioninformation will not be held. This is because it is assumed that themoving degree of the terminal device 10 is less than a predetermineddegree, and the importance of the position information is relatively nothigh.

When the time interval from the prior position information to theinterest position information is below the third time, the determinationunit 56 determines whether K times of the first moving speed from theprior position information to the interest position information isgreater than the second moving speed from the interest positioninformation to the posterior position information (S116). The firstmoving speed is the moving speed based on the time interval and thedistance between the prior position information and the interestposition information. The second moving speed is the moving speed basedon the time interval and the distance between the interest positioninformation and the posterior position information. “K” is any naturalnumber.

When K times of the first moving speed is the second moving speed orless, the process proceeds to step S110.

As S116 described above, when a change degree of the second moving speedis greater than that of the first moving speed, the interest positioninformation is assumed as noise. Thus, the interest position informationwill not be held.

When K times of the first moving speed is greater than the second movingspeed, the determination unit 56 determines whether a distance betweenthe prior position information and the interest position information isN1 [m] or more, or a distance between the interest position informationand the posterior position information is N2 [m] or more (S118). “N1”and “N2” are any desired natural numbers. “N1” and “N2” may be the samevalue or may be different values. When both conditions are not satisfiedin the process at S118, the process proceeds to S110.

As S118 illustrated above, when the distance between the interestposition information and the prior or posterior position information intime series is below a predetermined distance, the interest positioninformation will not be held. This is because it is assumed that themoving degree of the terminal device 10 is less than a predetermineddegree, and the importance of the position information is relativelylow. Alternatively, when the interval between the interest positioninformation and the prior or posterior position information in timeseries is a predetermined distance or more, the interest positioninformation will be held. This is because it is assumed that the movingdegree of the terminal device 10 is a predetermined degree or more, andthe importance of the position information is relatively high.

When at least one of the conditions is satisfied in the process at S118,the determination unit 56 determines whether the angle between vectors,which will be described in detail below, is equal to or more than θ(S120). When the angle between the vectors is below θ, the processproceeds to S110, and when the angle between the vectors is equal to ormore than θ, the process proceeds to S106. When there is no moreposition information to be acquired, the first routine of the presentflowchart will be finished.

When the process for determining whether to hold the interest positioninformation is performed as described above, it is possible to acquiremore accurate and meaningful position information.

The angle between the vectors will now be described with reference toFIGS. 6A and 6B. As illustrated in FIG. 6A, in the process at S120, whenan angle θ1 between a vector V1 directing from the prior positioninformation toward the interest position information and a vector V2directing from the interest position information toward the posteriorposition information is less than θ, it is possible to assume theinterest position information as noise. Consequently, the interestposition information will not be held.

On the other hand, as illustrated in FIG. 6B, in the process at S120,when an angle θ2 between the vector V1 directing from the prior positioninformation toward the interest position information and the vector V2directing from the interest position information toward the posteriorposition information is equal to or more than θ, it is assumed that theterminal device 10 is moving a predetermined degree or more.Consequently, the interest position information will be held.

The processes (processes from S102 to S120) in the flowchart explainedin FIG. 5 described above may also be applied to the time-seriesposition information (for example, position information 1 to N) for aplurality of times. FIG. 7 is a diagram illustrating an example of thecontents of position information when a process of the first to thirdroutines is performed on the position information at position IDs 1 toN. For example, when the process of the first routine on the positioninformation is executed at the position IDs 1 to N, and it is determinednot to hold the position ID 2, the processing target of the secondroutine is the position information excluding the position ID 2. Whenthe process of the second routine is executed on the positioninformation excluding the position ID 2, and it is determined not tohold the position ID 3, the processing target of the third routine isthe position information excluding the position ID 3 in addition to theposition ID 2. When the process of the third routine is executed on theposition information excluding the position ID 2 and the position ID 3,and it is determined not to hold the position ID 5, the positioninformation to be held in the end will be position information excludingthe position ID 5 in addition to the position ID 2 and the position ID3, among the position IDs 1 to N.

1-6. Omission of Determination Process in Each Routine

Among the determination processes (processes at S108 and S112 to S120)of the flowchart described in FIG. 5, a part of the processes may beomitted every time the routine is repeated. Moreover, the determinationprocess for omitting a part of the processes may differ in each routine.For example, when three routines from the first to third rounds areperformed, the processes in each routine may be changed as describedbelow.

For example, in the second-round routine, in the determination processesat S116 and S118, one or both of the determination processes may beomitted. Moreover, for example, in the third-round routine, only thedetermination process at S118 may be performed.

In the flowchart of FIG. 5, the determinations of the time, the speed,and the angle (determinations at S108, S112 to S116, and S120) may beperformed before the determination of the distance (determination atS118). The determination of the speed (determination at S116) may beperformed before the other determinations.

1-7. Conclusion

With the first embodiment described above, it is possible to properlysort the position information, by determining whether relation betweenone or more pieces of interest position information included in thetime-series position information acquired from the terminal distance andthe prior or posterior position information in time series satisfies thepredetermined criterion, and determining whether to hold the positioninformation on the basis of the determination result.

2. Second Embodiment

The second embodiment shows a reverse tendency to the first embodimentin the determination of the angle. However, when predetermined POI datais present within a predetermined range from the coordinates of theposition information, the position information is held even when theangle does not satisfy the predetermined criterion. Hereinafter,differences from the first embodiment will be described.

2-1. Configuration of Information Processing System in the SecondEmbodiment

FIG. 8 is a diagram illustrating a functional configuration example of aserver device 50A included in an information processing system 1A of thesecond embodiment. The server device 50A includes a storage unit 60Ainstead of the storage unit 60 of the server device 50 in the firstembodiment. The storage unit 60A stores therein map information 64. Forexample, the map information 64 includes point of interest (POI) dataindicating a specific place on the ground (for example, a station, arestaurant, a shop, an amusement park, an aquarium, a movie theatre, apark, and a vending machine), and information indicating the coordinatesaccording to the POI data. The specific place is an example of a “knownspecific location”.

Moreover, in addition to the functional configuration of the serverdevice 50, the server device 50A further includes a matching processingunit 58. The matching processing unit 58 searches the map information 64using the coordinates according to the position information stored inthe storage unit 60A, and determines whether predetermined POI data ispresent around the coordinates. The matching processing unit 58 thenoutputs the determination result to the determination unit 56.

The determination unit 56 determines whether to hold the target positioninformation on the basis of the processing result of the matchingprocessing unit 58.

2-2. Flowchart of Second Embodiment

FIG. 9 is a flowchart illustrating a part of the process flow in thesecond embodiment. Because S100 to S118 in the flowchart of FIG. 9 arethe same as S100 to S118 of FIG. 5, the illustration and explanationthereof will be omitted.

In the flowchart of FIG. 9, a process of S121 will be performed insteadof S120 in the flowchart of FIG. 5. At S121, the determination unit 56determines whether an angle between vectors is less than θ (S121). Theangle between the vectors is an angle between a vector directing fromthe prior position information toward the interest position information,and a vector directing from the interest position information toward theposterior position information. “θ” at S121 and “θ” at S120 in FIG. 5may be the same angle or different angles.

When the angle between the vectors is less than θ, the determinationunit 56 holds the interest position information (S106). This is becausedeviation is not generated between the interest position information andthe prior or posterior position information, the interest positioninformation will be held. When the angle between the vectors is not lessthan θ (when it is equal to or more than θ), the matching processingunit 58 searches the POI data of the map information 64 using thecoordinates of the posterior position information (S122). Next, thematching processing unit 58 determines whether predetermined POI data ispresent within a predetermined range from the coordinates of theposterior position information (S124).

When predetermined POI data is present within a predetermined range fromthe coordinates of the posterior position information, the processproceeds to S106. When predetermined POI data is not present within apredetermined range from the coordinates of the posterior positioninformation, the determination unit 56 determines not to hold theposition information (S111). The position information determined not tobe held at S111 is one or more pieces of position information among theprior position information, the interest position information, and theposterior position information. For example, when the angle between thevectors is equal to or more than θ, the posterior position informationis assumed as an outlier and may not necessarily be held. Consequently,the first routine of the present flowchart will be finished.

The position information determined not to be held at S111 may also bechanged according to the contents of the prior determination process.For example, the determination unit 56 may determine not to hold theinterest position information at S111, when the determination at S108 orS116 is negative. For example, the determination unit 56 may determinenot to hold the posterior position information at S111, when thedetermination at S124 is negative.

In the flowchart of FIG. 9 described above, the process proceeds to S111when the determination result at S108 and S116 is negative.Alternatively, the process may proceed to S122 when the determinationresult at S108 or S116 is negative.

2-3. Conclusion

In the second embodiment described above, even when it is determinedthat the position information does not satisfy the predeterminedcriterion, the position information is determined to be held assumingthat the predetermined condition has been met when predetermined POIdata is present within a predetermined range from the positioninformation. As a result, it is possible to prevent the positioninformation, which is not a real outlier, from being excluded as anoutlier.

3. Third Embodiment

In a third embodiment, the predetermined criterion is a criterionindicating that deviation is not generated between the interest positioninformation and the prior or posterior position information. Moreover,even when it is determined that the position information does notsatisfy the predetermined criterion, the determination unit 56 does notexclude the position information when the position information satisfiesa predetermined condition in which the position information is assumedas an exception. Hereinafter, the details will be described.

3-1. First Process Performed by Determination Unit

As an example that no deviation is generated between the interestposition information and the prior or posterior position information,the determination unit 56 determines whether the interest positioninformation is deviated from a reference locus that is obtained from thetime-series position information, for a predetermined degree or more.

FIGS. 10A and 10B are diagrams each explaining a process performed bythe determination unit 56 in the third embodiment (first example). Forexample, the determination unit 56 derives a reference locus Rf obtainedby performing regression analysis such as a least-squares method, on thetime-series position information (position information from time t totime t+4). When the position information is deviated from the calculatedreference locus Rf for a predetermined degree or more (when the shortestdistance of the position information from the reference locus Rf isdeviated a predetermined degree or more), the determination unit 56determines that the position information does not satisfy thepredetermined criterion and sets the position information as an outliercandidate. For example, the predetermined degree is obtained bycalculating the standard deviation of deviations of pieces of positioninformation from the reference locus Rf, and the deviation between theinterest position information and the reference locus is equal to ormore than plus and minus 2σ. “σ” is the standard deviation.

The determination unit 56 then inquires the matching processing unit 58whether a predetermined location is present within a predetermined rangefrom the outlier candidate. The determination unit 56 then acquires theprocessing result of the matching processing unit 58. When apredetermined location is not present within a predetermined range fromthe outlier candidate, the determination unit 56 sets the outliercandidate as an outlier.

Alternatively, as illustrated in FIG. 10B, when a predetermined locationC is present within a predetermined range from the outlier candidate,the determination unit 56 does not set the outlier candidate as anoutlier. This is because when a predetermined location is present withina predetermined range from the outlier candidate, the outlier candidateis not an outlier, but the user may be moving to stop at thepredetermined location.

3-2. Second Process Performed by Determination Unit

FIG. 11 is a diagram for explaining a process performed by thedetermination unit 56 in the third embodiment (second example). Forexample, the determination unit 56 selects vectors (V21 to V24) that aretemporally before last, last, next, and after next relative to a vectorVob, and when the angle formed with the average vector Va of the vectorsis within an angle range set in advance, sets the position informationat the base point of the vector Vob as an outlier.

The vector Vob is a vector directing from the interest positioninformation (in this example, position information at t+1) toward theposition information immediately posterior to the interest positioninformation (position information at t+2). The vector V21 is a vectordirecting from the position information at the time t−1 toward theposition information at the time t. The vector V22 is a vector directingfrom the position information at the time t toward the interest positioninformation. The vector V23 is a vector directing from the positioninformation at the time t+2 toward the position information at the timet+3. The vector V24 is a vector directing from the position informationat the time t+3 toward the position information at the time t+4.

When a predetermined location described above is present within apredetermined range from the interest position information that is to beexcluded as an outlier, the determination unit 56 may also determinethat the interest position information is not an outlier.

3-3. Process Performed by Information Management Unit

The information management unit 54 acquires the processing resultobtained when the determination unit 56 has performed processing on thetime-series position information acquired by a plurality of the terminaldevices 10. The information management unit 54 analyzes (integrallyprocesses) the processing result of the determination unit 56, andextracts the position information that commonly becomes an outlierbetween different terminals and at different times.

The information management unit 54 controls the communication unit 52 soas to send information alerting the presence of the extracted positioninformation that commonly becomes an outlier, to the manager's terminaldevice, which is not illustrated, used by the manager who manages theserver device. In this manner, for example, it is possible to alert themanager and the like.

The information management unit 54 may also send information inquiringthe user of the terminal device 10 if the user has actually been to theposition information that commonly becomes a common outlier.

When a response is received from the terminal device 10, the informationmanagement unit 54 can determine whether the extracted positioninformation that commonly becomes an outlier is a real outlier, or theposition information includes position information on a spot where theuser may drop by, on the basis of the acquired response information.When it is determined that the position information includes positioninformation on a spot (predetermined location) where the user may dropby, the determination unit 56 determines, when the position informationthat is suspected as a common outlier appears the next time, that theposition information that has appeared is not an outlier. Consequently,the determination unit 56 can more accurately determine whether theposition information is an outlier.

3-4. Conclusion

With the third embodiment described above, it is possible to properlysort the position information by excluding the position information asan outlier, when relation between the interest position information andthe prior or posterior position information in time series does notsatisfy a predetermined criterion.

In the embodiment described above, the server device 50 includes theinformation management unit 54, the determination unit 56, and thematching processing unit 58. However, the terminal device 10 may includethese functional units or these functional units may be dispersedlyprovided on each device.

In the embodiment described above, the server device 50 determineswhether to hold the position information. However, the server device 50may also determine whether to send the position information to the otherdevice using the position information. In this case, the other devicecan acquire the sorted position information.

In the embodiment described above, the server device 50 includes theinformation management unit 54 and the determination unit 56. Theinformation management unit 54 acquires the time-series positioninformation acquired by the terminal device 10. The determination unit56 determines whether relation between one or more pieces of interestposition information that are included in the time-series positioninformation acquired by the information management unit 54 and the prioror posterior position information in time series satisfies apredetermined criterion, and determines whether to hold the interestposition information based on the determination result. Consequently, itis possible to properly sort the position information.

In one aspect of the present invention, it is possible to properly sortthe position information.

Although the invention has been described with respect to specificembodiments for a complete and clear disclosure, the appended claims arenot to be thus limited but are to be construed as embodying allmodifications and alternative constructions that may occur to oneskilled in the art that fairly fall within the basic teaching herein setforth.

What is claimed is:
 1. An information processing device, comprising: aprocessor programmed to: acquire time-series position informationacquired by a terminal device; determine whether relation between one ormore pieces of interest position information included in the acquiredtime-series position information and prior or posterior positioninformation in time series satisfy a predetermined criterion, thepredetermined criterion indicating that no deviation is generatedbetween the interest position information and the prior or posteriorposition information; and determine whether to hold the interestposition information based on a determination result, wherein: upondetermining that the predetermined criterion is unsatisfied, theprocessor does not hold the interest position information.
 2. Theinformation processing device according to claim 1, wherein upondetermining that the predetermined criterion is unsatisfied, theprocessor does not hold the interest position information.
 3. Theinformation processing device according to claim 1, wherein thepredetermined criterion includes at least one of: a first criterion on atime interval between the interest position information and the prior orposterior position information, a second criterion on a distance betweenthe interest position information and the prior or posterior positioninformation, a third criterion on moving speed based on the timeinterval and the distance between the interest position information andthe prior or posterior position information, and a fourth criterion onan angle between a moving direction toward the interest positioninformation and a moving direction from the interest positioninformation.
 4. The information processing device according to claim 1,wherein the processor determines whether a time interval between theinterest position information and position information temporallyposterior to the interest position information is less than a firsttime, and when determining that the time interval is less than the firsttime, determines not to hold the interest position information.
 5. Theinformation processing device according to claim 4, wherein theprocessor determines whether the time interval between the interestposition information and the position information temporally posteriorto the interest position information is a second time that is longerthan the first time or more, and when determining that the time intervalis the second time or more, determines to hold the interest positioninformation.
 6. The information processing device according to claim 5,wherein when determining that the time interval between the interestposition information and the position information temporally posteriorto the interest position information is less than the second time thatis longer than the first time, the processor determines whether the timeinterval between the interest position information and positioninformation temporally prior to the interest position information is athird time or more, and when determining that the time interval is thethird time or more, determines to hold the interest positioninformation.
 7. The information processing device according to claim 1,wherein when first moving speed from the position information temporallyprior to the interest position information to the interest positioninformation is less than a criterion relative to second moving speedfrom the interest position information to the position informationtemporally posterior to the interest position information, the processordetermines not to hold the interest position information.
 8. Theinformation processing device according to claim 1, wherein when adistance between the interest position information and the positioninformation temporally prior to the interest position information or adistance between the interest position information and the positioninformation temporally posterior to the interest position information isless than a predetermined distance, the processor determines not to holdthe interest position information.
 9. The information processing deviceaccording to claim 1, wherein the processor determines whether an anglebetween the moving direction toward the interest position informationand the moving direction from the interest position information is lessthan a predetermined angle, and when the angle being formed is less thanthe predetermined angle, determines not to hold the interest positioninformation.
 10. The information processing device according to claim 1,wherein the processor repeatedly executes a process of selectinginterest position information from the time-series position informationand determining whether to hold the interest position information for aplurality of times, and omits a part of a determination process in aprocess of second round and onwards.
 11. The information processingdevice according to claim 1, wherein after determining to hold theinterest position information, the processor sets the positioninformation temporally posterior to the interest position information asinterest position information to be focused next, determines whetherrelation between at least the interest position information determinedto be held and the interest position information to be focused nextsatisfies the predetermined criterion, and determines whether to holdthe interest position information based on a determination result. 12.The information processing device according to claim 1, wherein afterdetermining not to hold the interest position information, the processorsets the position information temporally posterior to the interestposition information as interest position information to be focusednext, determines whether relation between at least the positioninformation that is temporally prior to the interest positioninformation determined not to be held and that is determined to be held,and the interest position information to be focused next satisfies thepredetermined criterion, and determines whether to hold the interestposition information based on a determination result.
 13. Theinformation processing device according to claim 1, wherein thepredetermined criterion is a criterion in which the interest positioninformation is prevented from being deviated from a reference locuscalculated from the time-series position information for a predetermineddegree or more.
 14. The information processing device according to claim1, wherein even when the position information is determined todissatisfy the predetermined criterion, the processor holds the positioninformation when a known specific location is present within apredetermined range from the position information.
 15. The informationprocessing device according to claim 14, wherein the processor acquiresthe time-series position information obtained by a plurality of theterminal devices, and the processor determines whether the acquiredposition information obtained by the plurality of the terminal devicessatisfies the predetermined criterion, and the processor extractsposition information that is a common outlier by analyzing thedetermination result, and that sets the position information that is acommon outlier as the known specific location.
 16. The informationprocessing device according to claim 15, wherein the processor controlsa communication device so as to send information alerting presence ofthe position information that is a common outlier, to a manager'sterminal device managed by a manager who manages the informationprocessing device.
 17. The information processing device according toclaim 15, wherein the processor controls the communication device so asto send inquiry information for inquiring whether the positioninformation that is a common outlier is an outlier, to the terminaldevice that has sent the position information.
 18. An informationprocessing method causing a computer to perform steps comprising:acquiring, by the computer, time-series position information obtained bya terminal device; determining, by the computer, whether relationbetween one or more pieces of interest position information included inthe acquired time-series position information and prior or posteriorposition information in time series satisfy a predetermined criterion,the predetermined criterion indicating that no deviation is generatedbetween the interest position information and the prior or posteriorposition information; and determining, by the computer, whether to holdthe interest position information based on a determination result,wherein: upon determining that the predetermined criterion isunsatisfied, the computer does not hold the interest positioninformation.
 19. A non-transitory computer readable storage mediumhaving stored therein a computer program that causes a processor toperform steps comprising: acquiring, by the processor, time-seriesposition information obtained by a terminal device; determining, by theprocessor, whether relation between one or more pieces of interestposition information included in the acquired time-series positioninformation and prior or posterior position information in time seriessatisfy a predetermined criterion, the predetermined criterionindicating that no deviation is generated between the interest positioninformation and the prior or posterior position information; anddetermining, by the processor, whether to hold the interest positioninformation based on a determination result, wherein: upon determiningthat the predetermined criterion is unsatisfied, the processor does nothold the interest position information.
 20. An information processingdevice, comprising: a processor programmed to: acquire time-seriesposition information acquired by a terminal device; determine whetherrelation between one or more pieces of interest position informationincluded in the acquired time-series position information and prior orposterior position information in time series satisfy a predeterminedcriterion; and determine whether to hold the interest positioninformation based on a determination result, wherein: the processordetermines whether a time interval between the interest positioninformation and position information temporally posterior to theinterest position information is less than a first time, and whendetermining that the time interval is less than the first time,determines not to hold the interest position information, the processordetermines whether the time interval between the interest positioninformation and the position information temporally posterior to theinterest position information is a second time that is longer than thefirst time or more, and when determining that the time interval is thesecond time or more, determines to hold the interest positioninformation, and when determining that the time interval between theinterest position information and the position information temporallyposterior to the interest position information is less than the secondtime that is longer than the first time, the processor determineswhether the time interval between the interest position information andposition information temporally prior to the interest positioninformation is a third time or more, and when determining that the timeinterval is the third time or more, determines to hold the interestposition information.
 21. An information processing method causing acomputer to perform steps comprising: acquiring, by the computer,time-series position information obtained by a terminal device;determining, by the computer, whether relation between one or morepieces of interest position information included in the acquiredtime-series position information and prior or posterior positioninformation in time series satisfy a predetermined criterion; anddetermining, by the computer, whether to hold the interest positioninformation based on a determination result, wherein: the computerdetermines whether a time interval between the interest positioninformation and position information temporally posterior to theinterest position information is less than a first time, and whendetermining that the time interval is less than the first time,determines not to hold the interest position information, the computerdetermines whether the time interval between the interest positioninformation and the position information temporally posterior to theinterest position information is a second time that is longer than thefirst time or more, and when determining that the time interval is thesecond time or more, determines to hold the interest positioninformation, and when determining that the time interval between theinterest position information and the position information temporallyposterior to the interest position information is less than the secondtime that is longer than the first time, the computer determines whetherthe time interval between the interest position information and positioninformation temporally prior to the interest position information is athird time or more, and when determining that the time interval is thethird time or more, determines to hold the interest positioninformation.
 22. A non-transitory computer readable storage mediumhaving stored therein a computer program that causes a processor toperform steps comprising: acquiring, by the processor, time-seriesposition information obtained by a terminal device; determining, by theprocessor, whether relation between one or more pieces of interestposition information included in the acquired time-series positioninformation and prior or posterior position information in time seriessatisfy a predetermined criterion; and determining, by the processor,whether to hold the interest position information based on adetermination result, wherein: the processor determines whether a timeinterval between the interest position information and positioninformation temporally posterior to the interest position information isless than a first time, and when determining that the time interval isless than the first time, determines not to hold the interest positioninformation, the processor determines whether the time interval betweenthe interest position information and the position informationtemporally posterior to the interest position information is a secondtime that is longer than the first time or more, and when determiningthat the time interval is the second time or more, determines to holdthe interest position information, and when determining that the timeinterval between the interest position information and the positioninformation temporally posterior to the interest position information isless than the second time that is longer than the first time, theprocessor determines whether the time interval between the interestposition information and position information temporally prior to theinterest position information is a third time or more, and whendetermining that the time interval is the third time or more, determinesto hold the interest position information.